They’re looking for volunteers:

1,112 volunteers, to be precise.

Half will be given the vaccine, half won’t. They’ll check back in a few months and see how many from group A got the virus, compared to how many from group B.

What’s interesting about this are the ethical questions involved. Obviously, the greatest good for the whole world would be if the trial proved the vaccine worked. But the trial will take time, for a couple of reasons.

The first reason is the simple one: They can give people the vaccine, but they can’t deliberately expose them to Covid 19. They just have to kind of perversely hope that enough people in both groups are exposed to it over time to be able to measure the difference between the two groups. An ideal result would be something like 70 people in the non vaccine group getting it, and nobody in the vaccinated group getting it.

Obviously, in a less free society, that wouldn’t be an issue. If you were using lab rats – real ones, or the North Korean, two legged variety – you would just inject every rat with the disease in a month’s time and see what happened. But you can’t do that with people in a western democracy.

But that means the trial will take time. How much time? Well:

“How quickly we reach the numbers required will depend on the levels of virus transmission in the community. If transmission remains high, we may get enough data in a couple of months to see if the vaccine works, but if transmission levels drop, this could take up to 6 months.”

That’s the other interesting paradox here. The more we contain and stop the spread of Coronavirus, the harder it becomes to see if a vaccine works, because as fewer people get it overall, fewer vaccine trial participants get it also. Which means it takes longer for the trial to work, and longer to get an answer.

And of course, six months isn’t the end of the process. Figuring out that the vaccine works is one thing – you then have to discover whether it’s actually safe, or has side effects. And you probably need a much larger group than 500 people for that. So even if this trial is positive, you’re probably going to have to wait another six months after that for a second trial, verifying safety, before this becomes widely available.

The best case scenario is a vaccine by year’s end. And that’s assuming everything works perfectly. In reality, it could be two years away, or more.

But still, we’ll take good news where we can get it.